When the Rangers return to the Garden ice Saturday afternoon for Game 1 of the Eastern Conference final against Tampa Bay, the ecstasy of their seven-game series win over Washington will have long evaporated, with nostalgia now dangerously nearby.

They will see Ryan Callahan, Brian Boyle and Anton Stralman, their former teammates and longtime friends, and a big reason for three losses to the Lightning this season, according to former Ranger Ron Duguay.

If the results are going to change, Duguay said the Rangers’ approach must as well, needing to save all handshakes for the line at the end of the series, turning any instinctive smiles into sneers.

“One thing needs to happen and happen early: They need to send a message to the former Rangers that they are not buddies and they’re going to be physical with them,” said Duguay, an analyst with MSG. “The Rangers have to look at them like they’re the enemy.

They need to know that they are not going to feel comfortable.”

No opposing player looked more comfortable in the regular-season meetings than Callahan, the former Rangers captain who had two-goal games in his first two contests against his former team, a player clearly treated differently than other opponents, according to Duguay.

Callahan, who missed the Lightning’s most recent game after undergoing an emergency appendectomy, was back on the ice with the team on Thursday, calling himself day-to-day and refusing to rule himself out for Game 1.

Whenever he returns, Duguay said it’s imperative the Rangers immediately shape how the series will be played.

“He was within a certain comfort zone playing against buddies, but that can’t happen anymore,” Duguay said. “Early on, a few Rangers have to go after him hard and let everyone see that he’s no longer a New York Ranger. Someone has to put a glove in the face and let the whole building know how it’s going to be.

“What I saw when he played against the Rangers, it can’t happen again. He can’t be allowed to create energy for the team. If I’m a coach, a big part of the conversation and preparation is they didn’t play him hard enough.”

The Rangers lost the three games by a combined 15-7 score and posted their two lowest shot totals of the season, while Henrik Lundqvist posted a 4.74 goals-against average and a .823 save percentage.

The three games, coming in a two-week span ending Dec. 1, ended with the Rangers at 11-9-4, but the four-plus month stretch that followed in which the Rangers finished 42-13-3 makes Joe Micheletti agree with Duguay that the early struggles will have no impact on the series.

“It’s not a bad matchup, not at all,” said Micheletti, who will be appearing on MSG pregame and postgame coverage with Duguay throughout the playoffs. “The games in the regular season, you can toss them out the window. The Rangers were an incomplete team then, but they’ve gotten healthier and the young guys have really come along. Tampa’s a dangerous team [but] I look at that as being five months ago.”

Lightning broadcaster Rick Peckham said the three wins were three of Tampa Bay’s 10 best games all season, citing them as the team’s most complete games, and the reminders of those results could make an immediate impact.

“They are playing with peak confidence,” Peckham said. “I’m sure if they look at the video of those games they’re gonna see themselves playing at an optimal level and they will remember how well they played. They are certainly capable of doing it again.”